TgJ Is4:5 :תְהֵי מַגְנָא עְלוֹהִי כִגנוּן‏ : it would be protection over it like a canopy
See the entire entry for gnō/ān, gnō/ū/ānā n.m. bridal chamber; canopy

TgJ Is4:5 :יַתִיר מִן יְקָרָא דַאְמִיר לְאֵיתָאָה עְלוֹהִי שְכִינְתָא תְהֵי מַגְנָא עְלוֹהִי כִגנוּן‏ : more than the glory that was said to bring the Shekhinah upon it, it will protect it like a canopy
See the entire entry for yattīr adj. excessive, extra